Fusible link



Jan. 26 1926. V 1,570,894

. v M. K. HOPKINS FUSIBLE LINK Filed l 21. 1919 2 shun-sum 1 Jab 72,55 e5,

Jan. 26 1926. I

M. K. HQPKINS FI JSIBLE LINK Filed July 21, 1919 v 2 Shoots-Shut 2 Patented Jan. 26, 1926.

UNITED TATES 1,570,894 PATENTOFFICE.

MORTON K. HOPKINS, OF. CHICAGO, ILLINOIS, ASSIGNOR '10 JOHN I1. KENNEDY, O 1! CHICAGO, IL INOIS- I p p FUsIBLn L NK.

To all whom it may] cancer n: y

Be it known that I, Monron' K. HOPKINS, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Fusible Links, .of which the following is a description. I My invention belongs to that general class of devices known as fusible links, which undernormal conditions are adapted to securely connect cooperating parts or mechanisms, but under abnormal conditions as to high temperature will release to allow the parts to separate. Suchdevices aroused for many purposes including those in connection with fire protection device-sand are particularly desirable and 'very 'gene'rally used in.

connection with automatic sprinkler heads. My improved link is peculiarly adapted to that use and wherever founddesirable.

The invention has among its objects the production of a device of the kind described that is simple and economical in construction, and is thoroughly efficient and reliable in use. To this end my invention consists in the novel construction, arrangement and combination of parts herein shown and described and more particularly pointed out in the claims.

In the drawings, wherein like reference characters indicate like or corresponding parts,

Fig. 1 is a face view of my improved link;

Fig. 2 is an edge view of the same showing the spacing means;

Fig. 3 is a longitudinal sectional view on the line 3--3 of Fig. 1;

Fig. 4 is a transverse section on line 4-4 of Fig. 1;

Fig. 5 shows the central portion of Fig. 8 enlarged to more clearly illustrate the construction;

Fig. 6 is a diagrammatic view of the parts to more clearly illustrate the construction;

Fig. 7 is a central sectional view showing the link as the parts separate; andv Fig. 8 is a face view of one of the plates.

In the drawings, 1, 2, represent duplicate plates each provided with an extending end 3 having an eye or loop or equivalent part 4 therein for engagement with the cooperating parts. These two plates are duplicates of one another, with the exception that the plate 1 is provided with an indentation 5 for the reception of a key, while the plate 2 is enlarging the cell at that .point.

provided with 'a' similar indentation 6 of smaller area than the indentation 5. The indentation 6 is provided in the wall on which. the strain comes as thetwo plates are pulled apart, with an angular face '7 of less depth than the indentation and. provided with an inclined face 8 extending from the face 7 to the level or face of the plate 2. Asthe two platesare placed together, it willthus be seen that the two parts 5 and 6 arebrought into partial registry with, one'a-not hento' form an L-shaped key way. 9 is the cooperatingL-sha'ped key 'provided on one side. with a part 10 adapted to loosely fit within the depression 5, and on'the'opposite'side with a smaller extension'll adaptedto fit as clearly indicated in Fig. 5, to leave a clearance space at the rear thereof to obviate any possibility of the arts tending to bind or stick as the parts isengage. The same effect may be secured by the reverse construction and providing clearance space by In the preferred construction also, each of the plates is provided with extensions 14 on the face which are simply intended as'spacing means to hold the two plates apart a sufficient distance to permit the proper positioning of the soft solder (not shown in the drawings) between the two. 1

It will thus be clearly seen from Figs. 3. 5, 6 and 7 that the key has a larger proportional area of its body positioned within the large cell 5 of one plate, with a smaller projecting portion positioned within the cell 6 of the other. This permits a part of the key, as at 15, to lie upon the face of the plate 2. The engagement of the projection of the key with the wall of the cell '6 is sufiicient to reliably maintain the parts in operative position when assembled, but upon slight movement in the direction of the pull of plate 1, as when the soft solder releases, will tend to lift the rear of the key, when the inclined face 12 will contact with the inclinedface 8 of the cell, instantaneously breaking the lock of the two and permitting the quick separation of the parts. This action also has a wedging effect as shown in Fig. 7, tending to forcibly separate the two Pla The entire device, as stated, is simple and economical in construction, there being only three parts, and has been found very effec tive and reliable in operation. It is obvious that slight modifications may be made without departing from the spirit of my invention, which broadly consists in the con struction of a device of the kind described consisting of but three essential parts, and in which the key is provided with a special wedging function as the solder is released, tending to positively separate the two plates and effectuate their practical operation.

Having thus described my invention, what I claim as new and desire to secure by Let-- ters Patent is:

1. A fusible link comprising opposed members, the said members each having a recessed part, which when brought into reg istration provides a keyway, one of said dopressions being of larger area than the other, the smaller depression being provided on an end wall with an inclined part connecting with the face of the plate, in combination with a cooperating key on one side formed to loosely seat in the smaller depression and having an inclined edge part, the space between said inclined part of the ke-yand wall of the recess being unobstructed whereby in separating movement the said inclined parts contact, said key having a part-thereof lying on the inner surface of the member having the smaller depression.

2. A fusible link comprising opposed members, the said members each having a re cessed part, which when brought into register provides a keyway, one of said depressions being of larger area than the other, the smaller depression being provided on an end wall with an angular part and an inclined portion extending from said angular part to the face of the plate, in combination with a cooperating key, on one side formed to loose- 1y seat in the smaller depression and provid ed wit-h a cooperating angular part forming a holding wall and an inclined edge portion, said last named side of the key having a part thereof lying on the face of the corresponding plate, the space between the inclined portions of the key and plate being unobstructed whereby they directly cooperate in the separating movement of the plates.

In testimony whereof, I have hereunto signed my name.

MORTON K. HOPKINS. 

